Windows XP or VIsta For New System?

[Atrocities]

What do you think?

$1595.00
-$80.00 rebate
$1515.00


CASE: CoolerMaster Stacker 830 Tower 420W Case W/ Side-panel Window
CPU: (Sckt775)Intel® Core™ 2 Duo E6320 CPU @ 1.86GHz 1066FSB 2x2MB L2 Cache 64-bit
MOTHERBOARD: (Quad-Core Supports) Asus P5N-E nForce 650i SLI Chipset LGA775 FSB1333 DDR2 Mainboard
MEMORY: (Req.DDR2 MainBoard)2GB (2x1GB) PC6400 DDR2/800 Dual Channel Memory (Corsair Value Select or Major Brand)
VIDEO CARD: NEW!!! NVIDIA GeForce 8800 GTS 320MB 16X PCI Express (Major Brand Powered by NVIDIA)
VIDEO CARD 2: NONE
LCD Monitor: NONE
HARD DRIVE: Single Hard Drive (500GB SATA-II 3.0Gb/s 16MB Cache 7200RPM HDD)
Data Hard Drive: 500GB SATA-II 3.0Gb/s 16MB Cache 7200RPM Hard Drive
Optical Drive: (Special Price) 18X DVD±R/±RW + CD-R/RW DRIVE DUAL LAYER (BLACK COLOR)
Optical Drive 2: 16X DVD ROM (BLACK COLOR)
SOUND: HIGH DEFINITION ON-BOARD 7.1 AUDIO

What do you think about water cooled CPU's? Never really considered one before. Are they dependable?

What about wireless net work cards? What is a good one?

Should I go with Vista, XP x64 (System is 64bit) or XP Pro?